.banner {
    margin: 100px auto;
}

.maxing img {
    width: 300px;
    height: 300px;
    display: block;
}

.imglist {
    width: 300px;
    display: flex;
    align-items: center;
    flex-wrap: nowrap;
}

.imglist li {
    width: 50px;
    height: 50px;
    padding: 5px;
    margin: auto 5px;
    border: 1px solid black;
}

.imglist li img {
    width: 50px;
    height: 50px;
    display: block;
}

.imglist li.active {
    border: 2px solid red;
}